JPH0324877Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a vane pump, such as a vane pump used for oil supply attached to an automatic transmission of an automobile.

(Prior art) A ring is arranged in a cylindrical bore of a pump housing having a suction path and a discharge path for fluid such as oil, and the ring is driven to rotate around an axis eccentric to the center of the ring. A rotor is disposed on the rotor, and a plurality of vanes are slidably moved in the radial direction of the rotor, and the outer end surface of the vane is always urged outward in the radial direction so that the outer end surface of the vane comes into close contact with the inner peripheral surface of the ring. By rotating this rotor, the inner circumferential surface of the ring, the outer circumferential surface of the rotor, the pair of adjacent vanes, and the upper and lower inner surfaces of the housing that sandwich the ring, rotor, and vanes in substantially contact with each other from above and below. A vane pump that rotates a pump chamber defined by
It is publicly known as disclosed in No.

In such a vane pump, since the rotor rotates eccentrically with respect to the ring, the volume of each pump chamber increases or decreases during rotation, and at the rotation angle position where the volume increases, the pump chamber communicates with the fluid suction path to pump fluid into the pump chamber. The fluid in the pump chamber is communicated with the fluid discharge passage at a rotational angular position where the volume is reduced and the fluid inside the pump is discharged to the discharge passage.

However, since the fluid in the fluid suction path is normally at atmospheric pressure, the pressure inside the pump when it is in communication with the suction path is atmospheric pressure, and the fluid in the fluid discharge path is at the discharge pressure, so the pressure within the pump chamber is atmospheric pressure. When the pump is in communication with the discharge passage, the pressure inside the pump chamber becomes a discharge pressure higher than the atmospheric pressure. Therefore, when the pump chamber at atmospheric pressure communicates with the discharge passage, or when the pump chamber at discharge pressure communicates with the suction passage, the pressure in the pump chamber changes significantly, and if this communication occurs suddenly, The pressure change also becomes rapid, and as a result, there is a problem in that a large amount of noise is generated.

In order to solve this problem, it is sufficient to gradually establish communication between the pump chamber and the discharge passage or suction passage to smooth out pressure changes during communication. A communication groove that communicates the pump chamber with the discharge path is formed in the ring surface facing the two parallel inner surfaces of the lumen, and the action of this communication groove connects the pump chamber to the discharge path. The present applicant previously filed an application for a vane pump (Utility Application No. 1983-44032) that allows for smooth pressure changes during communication.

However, in the vane pump according to this application, a communication groove is formed on the side surface of the ring as described above, and the communication groove opens on the inner peripheral surface of the ring over a predetermined angular range in order to communicate the pump chamber with the discharge path. Therefore, if the vane is tilted while the rotor is rotating, the edge portion of the outer end of the vane that faces the opening on the inner circumferential surface of the ring of the communication groove enters the opening, and the outer edge portion of the vane moves into the opening end. There was a problem in that noise was generated by collision with the vane (side wall surface of the communication groove) and the outer edge of the vane was easily damaged.

(Purpose of the invention) In view of the above circumstances, the purpose of the invention is to avoid collision between the outer edge of the vane and the open end of the inner peripheral surface of the ring of the communication groove formed on the side surface of the ring, thereby preventing noise generation. It is an object of the present invention to provide a vane pump which eliminates the risk of damage to edges.

(Structure of the invention) In order to achieve the above object, the vane pump according to the invention is provided from the side surface of the vane (the surface facing the two opposing parallel inner surfaces of the housing lumen) on the side facing the communication groove. The vane outer end surface region extending to a depth equal to or greater than the depth of the communication groove, that is, the vane outer end edge portion facing the ring inner circumferential surface opening of the communication groove, as the vane outer end edge portion faces the ring inner circumference facing the vane side surface. The inner circumferential surface area of the ring is formed as a tapered surface that is further away from the ring surface, or the inner circumferential surface area of the ring extends from the side surface of the ring side surface on which the communication groove is present to a depth equal to or greater than the depth of the communication groove. The vane is characterized in that it is formed as a tapered surface that is further away from the opposing vane outer end surface as it approaches the vane.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a front view showing an embodiment of the vane pump according to the present invention, excluding the cover-side housing, and FIG. 2 is a sectional view taken along the line -- in FIG. 1.

The illustrated vane pump includes a pump housing 3 consisting of a passage-side housing 1 and a cover-side housing 2. The passage-side housing 1 has a fluid suction passage 4 and a fluid discharge passage 5 formed therein. A cylindrical recess 6 with an opening at the upper end is formed,
The recess 6 is closed from above by the cover-side housing 2 to form a cylindrical housing inner cavity 3a. The inner cavity 3a is therefore defined by two mutually opposing and parallel housing inner surfaces 1a, 2a and a housing inner circumferential surface 3b.

A ring 7 is disposed within this housing inner cavity 3a. In the illustrated pump, this ring 7 has a cylindrical support pin 8 within the housing bore 3a.
It is disposed so as to be swingable in the directions of arrows A and B about the center 8a. This is intended to change the pump discharge amount by swinging the ring 7, and this point will be described later.
On one side surface of the ring 7, that is, on the lower surface 7d of the ring opposite to the housing inner surface 1a formed in the passage-side housing, there is a communication groove 32 for communicating the pump chamber 13 and the fluid suction passage 4, which will be described below.
and a communication groove 33 (shaded portion in FIG. 1) that communicates the pump chamber 13 and the fluid discharge path 5.
is formed. The suction passage side communication groove 32 opens facing the suction passage 4 on the ring outer peripheral surface 7c, and opens over a predetermined angular range facing the pump chamber 13 on the ring inner peripheral surface 7b. The discharge path side communication groove 33 is open facing the discharge device 5 on the ring outer circumferential surface 7c, and is open over a predetermined angular range facing the pump chamber 13 on the ring inner circumferential surface 7b.

In the space defined by the inner circumferential surface 7b of the ring and the two opposing inner surfaces 1a and 2a of the housing 3 that sandwich the ring from both upper and lower sides in a substantially abutting state, A rotor 1 is driven to rotate around an eccentric axis 10a.
0 is placed. The rotor 10 was fitted, via a bearing 24, into a boss portion 6a protruding from the bottom of a cylindrical recess in the passage-side housing near the center, and inserted into the rotor drive shaft insertion hole 2b of the cover-side housing. Rotor drive shaft (not shown)
is rotated in the direction of arrow C. Further, a plurality of grooves 10d in the rotor radial direction (hereinafter simply referred to as radial direction) are formed at equal intervals in the rotor circumferential direction on the outer circumferential portion of the rotor 10, and are opened in the rotor outer circumferential surface 10b. A circumferential groove 10e communicating with each radial groove 10d is provided on the upper surface of the
are formed on the lower surface of the rotor 10, and a circumferential groove 10f communicating with each radial groove 10d is formed on the lower surface of the rotor 10.
is formed.

A vane 11 is fitted into each of the radial grooves 10d so as to be slidable, that is, to be able to protrude and retract from the rotor outer peripheral surface 10b, and the vane 11 is fitted into a circumferential groove 10e formed on the upper surface of the rotor. A ring-shaped back-up spring 14 disposed inside
The high pressure oil introduced into the circumferential groove 10e via the high pressure oil introducer 12 formed in the cover side housing 2 (one end 12a of the introduction path is Since the opening faces the pump chamber in the discharge state, oil discharge pressure is guided into the circumferential groove 10e.)
As a result, the radially inner end surface 11b is pressed radially outward, and the radially outer end surface 11a is always in sliding contact with the ring inner circumferential surface 7b while being pressed.

Moreover, each vane 11 is - in FIG.
As shown in FIG. 3, which is a line sectional view, the depth a of the communication grooves 32, 33 is measured from the lower side surface 11c of the vane, which is the side surface of the vane opposite to the communication grooves 32, 33.
The region of the outer end surface 11a of the vane extending over the depth b is formed as a tapered surface 11e that is further away from the inner circumferential surface 7b of the ring as it goes toward the lower surface 11c of the vane.

Note that a protrusion 11f is provided on the back of the vane 11 on the side where the tapered surface 11e is provided. This protrusion 11f has a tapered surface 1
The inclination of 1e is actually slight and difficult to confirm at the time of assembly, so this is to facilitate this and to prevent incorrect assembly.

The space surrounded by the ring inner circumferential surface 7b, the rotor outer circumferential surface 10b, and the two opposing inner surfaces 1a and 2a of the housing is divided into a plurality of parts by the vane 11. Each space constitutes a pump chamber 13. The housing 3 is formed with a fluid suction passage port 15 and a fluid discharge passage port 16 for communicating the fluid suction passage 4 and the fluid discharge passage 5 with the pump chamber 13, respectively.

In such a vane pump, the rotor 10 is rotated in the direction of arrow C by the rotor drive shaft (not shown), and as a result, each pump chamber 13 also rotates in the direction of arrow C, and the volume of the pump chamber increases and decreases repeatedly. Each pump chamber 13 communicates with the suction passage port 15 to suck in fluid during the volume increase process, and communicates with the discharge passage port 16 during the volume reduction process to discharge fluid within the pump chamber toward the port 16. Further, the discharge amount changes in proportion to the rotational speed of the rotor 10, but also changes as the ring 7 swings in the directions of arrows A and B. That is, when the rotor rotation speed is constant, the illustrated state is the maximum discharge amount, and when the ring 7 swings in the direction of arrow A, the eccentricity between the ring 7 and the rotor 10 decreases, and the amount of eccentricity of the rotor 10 decreases. Pump chamber 13 during one revolution
Since the volume change amount decreases, the discharge amount also decreases. In the case of this embodiment, a flow rate control valve 18 consisting of a valve spring 18a and a spool 18b is disposed in the fluid discharge path 5, and the control fluid generated by the valve 18 according to the flow rate in the fluid discharge path 5. The pressure is guided through the control fluid pressure introduction path 19 formed in the passage-side housing 1 to the control fluid pressure 3c defined by the ring outer circumferential surface 7c, the housing inner circumferential surface 3b, and the seal members 20, 21. The control fluid pressure causes the ring 7 to swing in the direction of arrow A around the support pin 8, and the control fluid pressure generated when the discharge amount reaches a predetermined value _Q0 is applied to the spring 22. When Q exceeds ₀ , the control fluid pressure causes the ring 7 to swing by a predetermined angle in the direction of arrow A to reduce the discharge amount, as shown in Fig. 4. It is configured to control the discharge amount so that it does not exceed a predetermined value Q ₀ even if the rotor rotational speed increases.

In this embodiment, as described above, from the edge portion of the outer end surface 11a of the vane facing the communication grooves 32, 33, that is, from the lower surface 11c which is the side surface of the vane facing the communication groove, the depth a of the communication groove or more is depth b
A tapered surface 11 having a shape in which a region of the vane outer end surface 11a that extends further away from the opposing ring inner circumferential surface 7b as it goes toward the vane lower surface 11c side.
It is formed as e. Therefore, the vane 11 is moved to the third position due to the slight gap existing between the vane upper surface 11d and the housing inner surface 2a or between the vane lower surface 11c and the housing inner surface 1a.
The vane may be tilted in the direction of the arrow ED in the figure, for example, even if it is tilted in the direction in which the communication groove 32 exists (the direction of the arrow D), as shown in FIG. 5, which is an enlarged view of the tapered surface 11e of the vane in FIG. 3. As shown in FIG.
2a (see Figures 1 and 5).

In this embodiment, the outer end surface of the vane edge portion is formed into a tapered surface, but as shown by the two-dot chain line G in FIG. A tapered surface having a shape in which a ring inner circumferential surface region extending from the side surface 7d on the side where the communication groove is connected to a depth b that is greater than or equal to the depth a of the communication groove becomes further away from the opposing vane outer end surface as it goes toward the ring side surface 7d. It may also be formed as In this way, even if the outer end surface 11a of the vane edge portion has a conventional shape as shown by the two-dot chain line H in FIG.
There is no risk of collision.

In addition, in this embodiment, since both the communication grooves 32 and 33 are formed on the ring lower surface 7d, the vane also has only the outer end surface of the edge portion on the lower surface 11c side formed into a tapered surface. When it is formed on the side surface side, the tapered surface of the vane may also be formed on the upper side surface side of the vane, and when it is formed on both side surfaces of the ring, the tapered surface may be formed on both side surfaces of the vane. Regarding this point, the same applies to the case where a tapered surface is formed on the inner circumferential surface of the ring.

Furthermore, the ring may be of a fixed type that does not swing, in which case the ring may be integrated with the housing. The depth a of the communication groove can be, for example, 0.6 mm when the thickness of the ring 7 is 14 mm, and the depth b forming the tapered surface in this case can be, for example, 0.7 mm.

(Effects of the invention) As described above, the vane pump according to the invention has a predetermined depth region on the outer end surface of the vane on the side opposite to the communication groove formed on the ring side surface, or on the inner peripheral surface of the ring where the communication groove is formed. Since the predetermined depth region on the side where the vane is closed is formed as a tapered surface, there is a possibility that the outer edge of the vane enters the opening of the communication groove on the inner peripheral surface of the ring and collides with the side wall surface of the communication groove while the rotor rotates. Therefore, noise generation and damage to the vane edges can be avoided.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the vane pump according to the present invention, FIGS. 2 and 3 are sectional views taken along lines - and - in FIG. A diagram showing the relationship, FIG. 5, is an enlarged view of a part of FIG. 3. 1a, 2a...inner surface of pump housing, 3...
...Pump housing, 3a...Pump housing inner peripheral surface, 4...Fluid suction path, 5...Fluid discharge path,
7...Ring, 7b...Ring inner peripheral surface, 7c, 7
d... Ring side surface, 10... Rotor, 11... Vane, 11a... Vane outer end surface, 11c, 11d
...Vane side, 11e...Tapered surface, 13...
Pump chamber, 32, 33...communication groove.

Claims (1)

[Claims for Utility Model Registration] A pump housing having a fluid suction passage and a fluid discharge passage, a ring disposed within the pump housing, and the inner peripheral surface of the ring and the pump housing sandwiching the ring from both sides. A rotor disposed in a space defined by two opposing inner surfaces and driven to rotate around an axis eccentric to the center of the ring; and a plurality of vanes whose radially outer end surfaces are in sliding contact with the inner circumferential surface of the ring, and a pump chamber is defined by the inner circumferential surface of the ring, the outer circumferential surface of the rotor, and the vanes. and a vane pump configured such that fluid is sucked into the pump chamber from the fluid suction path and discharged from the pump chamber to the fluid discharge path by rotation of the rotor, the vane pump comprising: both sides of the ring; A communication groove that communicates the pump chamber with the fluid suction passage or the fluid discharge passage is formed in at least one of the vanes and is opened in the inner circumferential surface of the ring. A vane outer end surface region extending to a depth equal to or greater than the depth of the communicating groove or a ring inner circumferential surface region extending from the side surface of the ring on which the communicating groove is present to a depth equal to or greater than the depth of the communicating groove is located on the side of the side surface. 1. A vane pump characterized in that the vane pump is formed as a tapered surface that becomes further away from the opposing inner peripheral surface of the ring or the outer end surface of the vane.